* Important update to C-HARM in this bulletin. C-HARM version 3 is now operational at NOAA CoastWatch. Major changes include: new operational circulation model (WCOFS) for currents, salinity, and temperature and VIIRS ocean color products in place of MODIS Aqua. WCOFS is a 4DVAR data assimilative model run at NOAA Coast Survey Development Lab (CSDL). NOTE: There are serious issues with WCOFS salinity accuracy that have notable consequences for the Particulate Domoic Acid predictions; we will address the impact this has on pDA accuracy in these bulletins. Sensitivity analyses suggest that the impact of the shift to VIIRS for the ocean color inputs to C-HARM is small relative to the replacement of CA ROMS Classic with WCOFS (for salinity).
- C-HARM tells us where conditions are suitable for species of the diatom Pseudo-nitzschia spp. (all size classes) to grow well and where they might be more likely to produce the deadly neurotoxin, domoic acid (DA). Three independent models are run daily to produce nowcasts and three-day forecasts of the probability of a bloom, the probability of a DA event for particulate DA only, and the probability of a DA event for the cellular portion of DA only. Here, in the bulletin, we summarize nowcasts for the month.
- C-HARM predictions for Pseudo-nitzschia spp. blooms in February contain quite a lot of pixelation from VIIRS. Bloom potential is extremely high throughout the month, covering much of the California Current. An emphasis on higher risk in northern California emerges throughout the month as well as the Santa Barbara Channel and the Southern California Bight overall. The predictions for Pseudo-nitzschia corroborate something we've seen for a while in the California Current, which is that conditions are fairly regularly conducive to supporting Pseudo-nitzschia populations in most coastal zones.
- HABMAP weekly pier sampling in February indicates quite a lot of bloom potential for Pseudo-nitzschia spp. in southern California and the Santa Barbara Channel, but not so much in central or northern California according to the sparse sampling in that region. Both size classes bloomed at Stearns Wharf in Santa Barbara throughout February, and the larger more toxigenic size class exceeded bloom levels at Santa Monica Pier at the end of February. Levels of both size classes were quite high at Newport Beach Pier and Scripps Pier and appeared to be increasing in unison in response to similar environmental forcing.
- Pseudo-nitzschia activity from CDPH coastal sampling is consistent with a focus on southern California in February. 'Common' densities of the more toxigenic size class, Pseudo-nitzschia 'seriata,' were distributed at sites in the Santa Barbara region, LA and Orange County, and further south to La Jolla, and it was considered 'Present' at even more sites throughout the Southern California Bight.
- A selection of CA Imaging FlowCytobot (IFCB) Network images from the Bodega Marine Laboratory in northern California and from an offshore buoy at Del Mar (San Diego) in February illustrates the amazing latitudinal gradients from north to south that can be seen with this technology, as it collects images of the phytoplankton community every 30 minutes! Smaller classes of diatoms and some flagellates dominate at the Bodega Marine Lab intake in Horseshoe Cove, while large dinoflagellates and diatoms are more common at Del Mar as the upwelling season develops.
- C-HARM probabilities for particulate domoic acid (pDA) and cellular domoic acid (cDA) in February are most intense in central and southern California, and overlap between the two metrics is higher than it was in January. This may be a good indicator that pDA is not overestimating pDA event potential in the Bight relative to the classic ROMS version of the C-HARM, or it may indicate that both pDA and cDA risk are overestimated but for different reasons other than the salinity component of the prediction of pDA. One obvious difference is the low chance of cDA risk in northern California relative to that predicted for pDA in February. This lower risk is corroborated by measurements (albeit not too many). The lack of any DA measured at HABMAP pier sites, even in southern California, highlights both the difficulty in predicting DA from Pseudo-nitzschia bloom levels and the potential for mismatch in DA production between nearshore pier sites and offshore locations on the shelf.
- Animal strandings from potential DA toxicosis in February are consistent with C-HARM predictions of high DA risk in the Bight and HABMAP observations of bloom levels of the toxigenic size class at southern California pier sites. Two adult female California Sea Lions were recovered by the Marine Mammal Care Center of Los Angeles and by the Pacific Marine Mammal Center in Orange County.
- CDPH lifted an advisory on January 9 for mussels, scallops, and most types of clams in Humboldt County due to PSP and ASP. However, the advisory related to sport-harvested razor clams from Humboldt and Del Norte counties seems to remain in effect due to ASP risk. Given the low depuration (detox) rates of razor clams, DA levels in razor clams are usually more a reflection of long-term exposure to DA rather than real-time or recent bloom conditions. However, since this same advisory was lifted in June and then reinstated in November of this year, there has likely been persistent, if low-level, production of DA in the North Coast region.
- CDPH detected 'Rare' levels of Alexandrium spp. in February at one site in Humboldt Bay where HABMAP does not have a routine sampling site for Alexandrium. The lack of Alexandrium activity is, however, consistent overall with HABMAP, with only one record of detection at one site, Scripps Pier, in the entire month. In line with that, the Paralytic Shellfish Poisoning (PSP) advisory was lifted on January 9 for mussels, scallops, and most types of clams in Humboldt County.
Summary written by Clarissa Anderson on 10 April 2023
Note that data for some stations are not shown because they are not yet recorded in the public HABMAP archive.
Differentiating Pseudo-nitzschia species by light microscopy is difficult. For this reason, Pseudo-nitzschia "seriata" does not refer to an actual species but rather the larger size class of Pseudo-nitzschia, which is generally a more toxigenic group of species. Alternatively, Pseudo-nitzschia "delicatissima" refers to the smaller size class that is generally non-toxigenic. The dashed line on the plots demarcates the 10,000 cells/L "bloom" threshold designated here for Pseudo-nitzschia populations only.
Four water samples were collected at the Bodega Marine Lab shore station in February. Pseudo-nitzschia "delicatissima" was detected twice (February 6, 13) below the bloom threshold. Pseudo-nitzschia "seriata" and Alexandrium spp. were not detected. Domoic acid results are pending.
The Bodega Marine Lab shore station is supported by CeNCOOS PI John Largier.
One water sample was collected at the Bodega Marine Lab Buoy station in February. Pseudo-nitzschia "delicatissima" was not detected. Pseudo-nitzschia "seriata" was detected on February 25, below the bloom threshold. Alexandrium spp. were not detected and domoic acid results are pending.
The Bodega Marine Lab Buoy shore station is supported by CeNCOOS PI John Largier.
Four water samples were collected at Santa Cruz Wharf in February. Molecular probes for toxigenic Pseudo-nitzschia in the "seriata" class are conducted for this site, and was not detected. Alexandrium spp. were also not detected. Domoic acid was not detected in the first sample (February 1) with the remaining results pending.
The Santa Cruz Wharf shore station is supported by CeNCOOS PI Raphael Kudela at UCSC
Four water samples were collected at Monterey Wharf in February. Pseudo-nitzschia "delicatissima" was detected on February 22, below the bloom threshold. Pseudo-nitzschia "seriata" was detected on three occasions (February 1, 8, 22). Alexandrium spp. were not detected. Domoic acid results are pending.
Monterey Wharf shore station is supported by CeNCOOS.
Four water samples were collected at Cal Poly Pier in February. Pseudo-nitzschia "delicatissima" was detected once on February 13, below the bloom threshold. Pseudo-nitzschia "seriata", Alexandrium spp., and domoic acid were not detected.
Cal Poly Pier shore station is supported by SCCOOS and PI Ally Pasulka at Cal Poly.
Four water samples were collected at Stearns Wharf in February. Pseudo-nitzschia "delicatissima" was detected each time (February 2, 15, 21, 27), with the last two samples above the bloom threshold. Pseudo-nitzschia "seriata" was detected twice (February 21, 27), with the first sample above the bloom threshold. Alexandrium spp. and domoic acid were not detected.
Stearns Wharf is supported by SCCOOS and PIs Mark Brzezinski and Libe Washburn at UCSB.
Four water samples were collected at Santa Monica Pier in February. Pseudo-nitzschia "delicatissima" was detected on each occasion (February 6, 13, 20, 27), all below the bloom threshold. Pseudo-nitzschia "seriata" was detected on three occasions (February 6, 13, 20), with Feb 20 above the threshold. Alexandrium spp. and domoic acid were not detected.
The Santa Monica Pier shore station is supported by SCCOOS and PI Rebecca Shipe at UCLA.
Four water samples were collected at Newport Beach Pier in February. Pseudo-nitzschia "delicatissima" was detected on three occasions (February 6, 21, 28), all above the bloom threshold. Pseudo-nitzschia "seriata" was detected on each occasion (February 6, 13, 21, 28), with Feb 21, 28 above the threshold. Alexandrium spp. and domoic acid were not detected.
Newport Beach Pier is supported by SCCOOS and PI David Caron at USC.
Four water samples were collected at Scripps Pier in February. Pseudo-nitzschia "delicatissima" and Pseudo-nitzschia "seriata" were detected each time (February 6, 13, 21, 27), all above the threshold except for Feb 13. Alexandrium spp. were detected twice (February 13, 21). Domoic acid was detected on February 21 and 27.
Scripps Pier is supported by SCCOOS and PIs Melissa Carter and Clarissa Anderson at UCSD.
View the interactive map and data table of California Department of Public Health (CDPH) data from January 2019 to present, developed by SCCOOS, below. Or, view CDPH Toxic Phytoplankton Observations Map with layers of Pseudo-nitzschia and Alexandrium spp. as well as other phytoplankton species observations (in the pop-up windows).
Data are provided by the Environmental Management Branch of the CDPH. Please note, starting in July 2019, CDPH moved to only reporting Pseudo-nitzschia of the seriata complex and not all Pseudo-nitzschia spp. as previously provided.
Please email CDPH at Thomas.Hayashi@cdph.ca.gov for any potential marine HAB-related illness in humans.
From February 1-28 2023, water samples were collected by volunteers and sent to the California Department of Public Health (CDPH) for analysis.
Pseudo-nitzchia "seriata" group was detected in 23 of the 72 samples:
Pseudo-nitzschia "seriata" was detected at "Common" density levels on 7 occasions:
- 2023-02-13 10% La Jolla, Scripps Pier
- 2023-02-17 10% Santa Barbara, Mohawk Reef
- 2023-02-17 12% Redondo Beach Breakwater
- 2023-02-17 15% Palos Verdes, OFFSHORE
- 2023-02-21 14% La Jolla, Scripps Pier
- 2023-02-21 40% Goleta Pier
- 2023-02-27 21% La Jolla, Scripps Pier
Pseudo-nitzschia "seriata" was detected at "Present" density levels on 8 occasions:
- 2023-02-06 1% La Jolla, Scripps Pier
- 2023-02-08 1% Goleta Pier
- 2023-02-15 1% Manhattan Beach Pier
- 2023-02-15 2% Pacific Beach Pier
- 2023-02-16 1% Imperial Beach Pier
- 2023-02-16 3% Marina Del Rey
- 2023-02-22 8% Imperial Beach Pier
- 2023-02-24 7% Bolsa Chica
Pseudo-nitzschia "seriata" was detected at "Rare" density levels on 8 occasions:
- 2023-02-01 0.5% Goleta Pier
- 2023-02-02 0.5% Redondo Beach Pier
- 2023-02-03 0.5% Bolsa Chica
- 2023-02-04 0.5% Palos Verdes Rocky Pt Offshore
- 2023-02-06 0.5% Tomales Bay, Lease #M430-15
- 2023-02-08 0.5% Santa Cruz Wharf
- 2023-02-10 0.5% Bolsa Chica
- 2023-02-15 0.5% Crystal Cove SB, OFFSHORE
Alexandrium spp. were detected in 1 of the 72 samples:
Alexandrium spp. were not detected at "Common" density levels.
Alexandrium spp. were not detected at "Present" density levels.
Alexandrium spp. were detected at "Rare" density levels once:
- 2023-02-06 0.5% Humboldt Bay, Indian Is. Ch.
CDPH and OEHHA Health Advisories
January 9. The California Department of Public Health (CDPH) has lifted the shellfish safety notification today related to sport-harvested mussels, scallops, and most types of clams in Humboldt County. An advisory for razor clams in Humboldt County remains in effect.
December 12. The California Department of Public Health (CDPH) has lifted the shellfish safety notifications today related to sport-harvested mussels, scallops, and clams in San Mateo, Monterey, and San Luis Obispo counties.
October 31. The California Department of Public Health (CDPH) announced the statewide annual quarantine on mussels taken by sport harvesters from California’s ocean waters ends at midnight on Monday, October 31, 2022, for all coastal counties except Humboldt, San Mateo, Monterey, and San Luis Obispo.
For the latest closures and updates, please visit the CDPH Health Advisories page as a central location of information related to CDPH health advisories. Also available is a map showing the current CDPH Recreational Bivalve Shellfish Advisories (see below).
A network of Imaging FlowCytobots (IFCBs) continuously photographs particles, such as plankton, in the water. Using machine learning, plankton species can be automatically identified. This will help improve the ability to detect and respond to Harmful Algal Blooms, including the ability to assess conditions that may lead to toxin production or blooms of toxin-producing algae.
Additional images and data are available on the IFCB dashboard.
A mosaic of images from Bodega Marine Lab and the Del Mar Mooring in February.
Domoic acid (DA) is a potent neurotoxin produced by some diatom species of the genus Pseudo-nitzschia. Species exposed to DA can result in seizures, epilepsy, cardiomyopathy, and death depending upon the ingested dose. DA toxicosis commonly occurs in California Sea Lions (Zalophus californianus), presumably due to a combination of foraging behavior and seasonal movements. The Marine Mammal Center (TMMC), Channel Islands Marine Wildlife Institute (CIMWI), California Wildlife Center (CWC), Marine Mammal Care Center Los Angeles (MMCC-LA), Marine Animal Rescue (MAR), the Pacific Marine Mammal Center (PMMC), SeaWorld, and Southwest Fisheries Science Center (SWFSC) act like an emergency room by working to rescue and rehabilitate sick and injured marine mammals, seabirds, and sea turtles.
CWC, CIMWI, TMMC, SWFSC, and SeaWorld did not record any strandings due to suspected domoic acid in February 2023.
February strandings due to suspected DA toxicosis occurred in the following counties:
- Los Angeles (MMCCLA and PMMC)
- February 11 - Adult, female, California Sea Lion
- February 26 - Adult, female, California Sea Lion